Electronic device that includes a composition that can actively generate and release a gaseous oxidizing agent component into an interior space of the electronic device, and related subassemblies and methods

ABSTRACT

The present disclosure relates to electronic devices that include a composition that actively generates a gaseous oxidizing agent component within the interior gas space of the electronic device. The present disclosure also involves related methods.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional patent application of Ser. No.17/583,746 filed on Jan. 25, 2022, and published as U.S. Pub. No.2022/0148626 (Luebben et al.), which is a continuation-in-part patentapplication of nonprovisional patent application Ser. No. 17/325,980filed on May 20, 2021, and published as U.S. Pub. No. 2021/0287719(Luebben et al.), which is a continuation patent application ofnonprovisional patent application Ser. No. 16/944,573 filed on Jul. 31,2020, now U.S. Pat. No. 11,024,343, which in turn claims the benefit ofcommonly owned provisional applications: Ser. No. 62/884,027, filed onAug. 7, 2019; and Ser. No. 62/936,816, filed on Nov. 18, 2019; whereinthe entirety of each of said applications is incorporated herein byreference.

The present application is related to patent application havingapplication Ser. No. 16/944,516 filed on Jul. 31, 2020, by Luebben etal., titled “ELECTRONIC DEVICE THAT INCLUDES A COMPOSITION THAT CANRELEASE AND OPTIONALLY GENERATE A GASEOUS OXIDIZING AGENT COMPONENT INTOAN INTERIOR SPACE OF THE ELECTRONIC DEVICE, AND RELATED SUBASSEMBLIESAND METHODS”, wherein the entirety of said nonprovisional application isincorporated herein by reference.

BACKGROUND

The present disclosure relates to electronic devices such as datastorage devices like hard disk drives (HDDs) (internal and/or external),network attached storage (NAS), and the like. There is a continuing needto solve problems related to maintaining internal, electronic drivecomponents in as-built conditions for the service life of the electronicdevice.

SUMMARY

The present disclosure includes embodiments of an electronic deviceincluding:

-   -   a) a housing having an interior gas space;    -   b) one or more electronic components disposed within the        housing;    -   c) a composition that can actively generate a gaseous oxidizing        agent component, wherein the composition comprises a stabilizer        that can slow down the generation of the gaseous oxidizing        agent; and    -   d) a generating device configured to actively cause the        composition to generate the gaseous oxidizing agent component.

The present disclosure also includes embodiments of an electronic deviceincluding:

-   -   a) a housing having an interior gas space;    -   b) one or more electronic components disposed within the        housing;    -   c) a composition that can actively generate a gaseous oxidizing        agent component; and    -   d) a generating device configured to actively cause the        composition to generate the gaseous oxidizing agent component,        wherein the generating device includes one or more heating        elements in thermal contact with the composition, wherein the        one or more heating elements are in electrical communication        with a power source that is configured to apply power to the one        or more heating elements to heat the composition to a        temperature that causes the composition to generate the gaseous        oxidizing agent component.

The present disclosure also includes embodiments of an electronic deviceincluding: a) a housing having an interior gas space;

-   -   b) one or more electronic components disposed within the        housing;    -   c) a composition that can actively generate a gaseous oxidizing        agent component; and    -   d) a generating device configured to actively cause the        composition to generate the gaseous oxidizing agent component,        wherein the composition is disposed within a housing, wherein        the housing comprises at least a first wall and a concentric,        second wall defining a space between the first wall and the        second wall, wherein the housing is thermally insulating, and,        optionally, wherein the housing is disposed within an        environmental control module.

The present disclosure also includes embodiments of an electronic deviceincluding:

-   -   a) a housing having an interior gas space;    -   b) one or more electronic components disposed within the        housing;    -   c) a composition that can actively generate a gaseous oxidizing        agent component; and    -   d) a generating device configured to actively cause the        composition to generate the gaseous oxidizing agent component,        wherein the composition has been pre-conditioned by a process        comprising heating the composition to a temperature that causes        the composition to generate a gaseous oxidizing agent component,        wherein the heating occurs for a time period that corresponds to        an increase in rate of weight loss of the composition for a        temperature from a first rate of weight loss of the composition        to a second rate of weight loss of the composition, wherein the        second rate of weight loss is less than a maximum rate of weight        loss at the temperature.

The present disclosure also includes embodiments of an electronic deviceincluding:

-   -   a) a housing having an interior gas space;    -   b) one or more electronic components disposed within the        housing;    -   c) a composition that can generate a gaseous oxidizing agent        component; and    -   d) a generating device configured to actively cause the        composition to generate the gaseous oxidizing agent component,        wherein the generating device includes at least one metal-air        battery that is in electrical communication with a power source        that is configured to apply power to the metal-air battery        according to a predetermined time interval to recharge the        metal-air battery to generate the gaseous oxidizing agent        component.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a cross-section schematic of one embodiment of a devicefor actively generating a gaseous oxidizing agent component;

FIG. 1B shows a cross-section schematic of another embodiment of adevice for actively generating a gaseous oxidizing agent component;

FIG. 2 shows a schematic representation of a metal air battery that canbe used in an electronic device according to the present disclosure;

FIG. 3 shows a non-limiting example of a dual chamber container 300 witha permeation layer and micro-valve, which works like a 2-stageregulator;

FIGS. 4A-4D illustrate one non-limiting embodiment according to thepresent disclosure of including a composition that can generate agaseous oxidizing agent component into a hard disk drive

FIG. 5 illustrates another non-limiting embodiment according to thepresent disclosure of including a composition that can generate agaseous oxidizing agent component into a hard disk drive;

FIG. 6 illustrates another non-limiting embodiment according to thepresent disclosure of including a composition that can be activelycontrolled to generate a gaseous oxidizing agent component into a harddisk drive;

FIGS. 7A-7N illustrate another non-limiting embodiment according to thepresent disclosure of including a composition that can be activelycontrolled to generate a gaseous oxidizing agent component in a harddisk drive;

FIG. 8 shows a partial, cross-sectional, perspective schematic of analternative embodiment of the generating device shown in FIG. 7N;

FIG. 9 shows a partial, cross-sectional, perspective schematic ofanother alternative embodiment of the generating device shown in FIG.7N;

FIG. 10 shows a partial, cross-sectional, perspective schematic ofanother alternative embodiment of the generating device shown in FIG.7N; and

FIG. 11 shows a partial, cross-sectional, perspective schematic ofanother non-limiting embodiment according to the present disclosure ofincluding a composition that can be actively controlled to generate agaseous oxidizing agent component in a hard disk drive.

DETAILED DESCRIPTION

The present disclosure relates to electronic devices that include acomposition that is actively controlled to generate a gaseous oxidizingagent component within the interior gas space of the electronic device.The present disclosure also relates to electronic devices that include acontainer that includes a gaseous oxidizing agent component in a mannerthat the gaseous oxidizing component can transfer from the container tothe interior gas space of the electronic device.

A wide variety of electronic devices having an interior space and one ormore electronic components disposed within the interior space canbenefit by having a container that includes a gaseous oxidizing agentcomponent that can be released into the interior space and/or acomposition that generates a gaseous oxidizing agent component after theelectronic device is assembled and during at least a portion of itsservice life as described herein. In some embodiments, an electronicdevice is a data storage device. Non-limiting examples of data storagedevices include hard disk drives (internal and/or external), networkattached storage (NAS), and the like. Examples of hard disc drives arereported in U.S. Pat. No. 7,478,760 (Beatty et al.) and U.S. Pat. No.7,695,547 (Smith), wherein the entireties of said patents areincorporated herein by reference.

For example, in some embodiments, for desirable performance andreliability characteristics in disk drives an operating atmosphere caninclude an initial fill of a gas mixture that includes primarily heliumgas and a second minor gas fraction consisting of a gaseous oxidizingagent component (oxidizer) for the entire operational life of the drive.The purpose of the primarily helium environment is to reduce gasturbulence induced vibration of the drives internal components tofacilitate track follow capability across disk track widths of 100 nm orless. The second minor gas component, the gaseous oxidizing agentcomponent can oxidize inorganic and/or organic materials and limit theiraccumulation on one or more components within the interior of anelectronic device such as a hard disk drive as desired (e.g., tomaintain one or more electronic components within the interior space inas-built conditions). Chemical reactions between the gaseous oxidizingagent component and inorganic and/or organic materials is believed toresult in the formation of gaseous by-products that are free totransport away.

It has been observed that the concentration of an initial quantity ofoxygen gas included in welded HDDs can unfortunately decrease over time.The rate of decrease of oxygen concentration can depend on a variety offactors such as one or more drive operating conditions. The loss ofoxygen over time can be attributed to chemical reactions between oxygenand internal drive components. Such internal drive components include,but are not limited to, the recording media, activated carbon, andferrous metal components. The measured rate of loss of oxygen isexpected to result in the oxygen concentration dropping below a desiredconcentration over the service life of the HDD.

The interior gas space of an electronic device can include helium gas tomaintain sufficient vibration mitigation. As the fraction of helium isdecreased (e.g., from 100%), the vibrational performance of the drivemechanics can degrade, suggesting it can be beneficial to limit thenon-helium oxidizing gas constituents to a minimum mole fraction asdesired. the helium gas is present in the interior gas space at a molefraction of 99 percent or less based on the total gas in the interiorgas space (e.g., from 80 to 99 percent, from 80 to 95 percent, from 85to 95 percent, or even from 85-90 percent).

The interior gas space of an electronic device can have a nominalrelative humidity of 20% or less at 25° C., 15% or less at 25° C., 10%or less at 25° C., 5% or less at 25° C., or even 1% or less at 25° C.

In some embodiments, an electronic device can be a hermetically sealedelectronic device, which can be defined by, e.g., the amount of gas thatleaks from the electronic device after it has been sealed (e.g., awelded HDD). In some embodiments, the interior gas space includes heliumgas and the hermetically sealed electronic device has a helium leak rateof 50×10{circumflex over ( )}−8 atm (atmosphere) cc (cubiccentimeter)/second or less at 25° C.; 20×10{circumflex over ( )}−8 atmcc/second or less, 10×10{circumflex over ( )}−8 atm cc/second or less;5×10{circumflex over ( )}−8 atm cc/second or less at 25° C.; or even4.2×10{circumflex over ( )}−8 atm cc/second or less at 25° C.

The present disclosure involves maintaining the concentration of agaseous oxidizing agent component in the interior gas space of anelectronic device within a desirable range over a variety of operatingconditions and for a given time period (e.g., throughout the life of thedrive). Maintaining a gaseous oxidizing agent component has theadvantage of maintaining the helium mole fraction at a desired level tohelp provide a favorable mechanical vibration environment, while at thesame time maintaining a desired supply of a gaseous oxidizing agentcomponent to reduce or prevent performance impairment of one or moreinternal, electronic drive components due to insufficient oxidizersupply.

According to one aspect, the present disclosure includes approaches foractively generating a gaseous oxidizing agent component from acomposition at a rate selected to maintain a desired concentration ofthe gaseous oxidizing agent component as described herein. As usedherein, “a gaseous oxidizing agent component” includes one or moreoxidizing agent species. Nonlimiting examples of oxidizing agent speciesinclude atomic oxygen, molecular oxygen, ozone, nitrous oxide, hydrogenperoxide, oxygen radical, dioxygen radicals, and mixtures thereof.

A type and amount of a composition that generates a gaseous oxidizingagent component can be selected based on one or more factors such as thetarget mole fraction of gaseous oxidizing agent component in theinterior space of an electronic device; the temperature or range oftemperatures at which the composition generates a gaseous oxidizingagent component; the operating temperature of an electronic device,which the composition will be exposed to; the service life of theelectronic device; and the like. In some embodiments, the compositioncan be included in an electronic device that has been initially filledwith a gas mixture of helium/oxidizing gas species when initiallyassembled.

In some embodiments, a composition that generates a gaseous oxidizingagent component is selected to be a type and in an amount to generate agaseous oxidizing agent component so that the gaseous oxidizing agentcomponent is maintained in the interior gas space at a mole fraction inthe range from 0.1 to less than 20 mole percent based on the total gasin the interior gas space; a mole fraction in the range from 0.1 to 15mole percent based on the total gas in the interior gas space; a molefraction in the range from 0.1 to 10 mole percent based on the total gasin the interior gas space; a mole fraction in the range from 0.1 to 5mole percent based on the total gas in the interior gas space; a molefraction in the range from 0.5 to 5 mole percent based on the total gasin the interior gas space; a mole fraction in the range from 0.5 to 4mole percent based on the total gas in the interior gas space; or even amole fraction in the range from 1.5 to 3 mole percent based on the totalgas in the interior gas space.

A composition that generates a gaseous oxidizing agent component isselected to be a type and in an amount to generate a gaseous oxidizingagent component so that the gaseous oxidizing agent component ismaintained in the interior gas space at a desired mole fraction for adesired time period after the electronic device (e.g., hard disk drive)has been finally assembled and ready for service (e.g., at least aportion of the service life of the hard disk drive). In someembodiments, a composition that generates a gaseous oxidizing agentcomponent is selected to be a type and in an amount to generate agaseous oxidizing agent component so that the gaseous oxidizing agentcomponent is maintained in the interior gas space at a desired molefraction for a time period of at least two months, or even at least sixmonths. In some embodiments, a composition that generates a gaseousoxidizing agent component is selected to be a type and in an amount togenerate a gaseous oxidizing agent component so that the gaseousoxidizing agent component is maintained in the interior gas space at adesired mole fraction for a time period of up to 3 years, up to 4 years,up to 5 years, up to 6 years, up to 7 years, up to 8 years, or even upto 9 years.

According to the present disclosure, a composition can be used toactively generate the gaseous oxidizing agent component. As used herein,“active” generation of gaseous oxidizing agent component refers to thecontrolled application of active mechanisms such as one or more of heat,light, electrochemical, injected electrons and/or water to oxygenliberating compounds to control the rate at which oxygen is produced.Active generation of gaseous oxidizing agent component is in contrast topassive generation of gaseous oxidizing agent component, which refers tothe decomposition of materials or reaction of two or more compoundsthrough their inherent physical and chemical properties resulting in theproduction of a gaseous oxidizing agent component.

A composition that generates a gaseous oxidizing agent component isselected to be a type and in an amount to activate the generation agaseous oxidizing agent component at a desired rate at one or moretemperatures above typical temperatures at which an electronic deviceoperates at, thereby actively controlling the generation of gaseousoxidizing agent component. In some embodiments, a composition thatgenerates a gaseous oxidizing agent component is selected to be a typeand in an amount to generate a gaseous oxidizing agent component at adesired rate at a temperature greater than 60° C., greater than 80° C.,greater than 100° C., greater than 110° C., or even greater than 120° C.In some embodiments, a composition that generates a gaseous oxidizingagent component is selected to be a type and in an amount to generate agaseous oxidizing agent component at a desired rate at a temperature inthe range from 100° C. to 200° C., from 110° C. to 180° C., or even from120° C. to 160° C. In some embodiments, the composition can be selectedso that it generates a gaseous oxidizing agent component at a sufficientrate so that the composition can last for a desired portion of theservice life of the electronic device, as described above, while at thesame time produce enough gaseous oxidizing agent component while thecomposition is activated to generate the gaseous oxidizing agentcomponent.

Non limiting examples of generating oxidizing agent species areillustrated below. For example, Equations 1, 2, 3 and 4 below illustrateoxidizing agent species C that can be generated according to the presentdisclosure. In some embodiments, the oxidizing agent species C ismolecular oxygen (O₂) and/or nitrous oxide due to their favorablestability.

In addition to the active mechanisms mentioned above to facilitategenerating oxidizing agent species, one or more chemical components canbe included in the chemical composition to modify the chemical reaction.In some embodiments, the rate of decomposition of A may be acceleratedchemically. For example, a catalyst may be used to accelerate the rateof decomposition of A. In some embodiments, the rate of decomposition ofA may be slowed down chemically. For example, a stabilizer may be usedto slow down the rate of decomposition of A.

In some embodiments, as discussed below, if the decomposition of Aoccurs within a housing or container disposed in an electronic device. Acontainer may include a barrier material (e.g., film) that can controlthe rate of diffusion of the oxidizing agent species C to the interiorspace of the data storage device where it can oxidize inorganic andorganic materials of transducer structures as desired.

In equations 1-4 below, A is a chemical composition for generating theoxidizing agent species C in the drive, B is a byproduct of thedecomposition, C is the oxidizing agent species, D is a secondarybyproduct of decomposition, and E is a catalyst, a stabilizer and/or abarrier. Non-limiting examples of by-products B and D include but arenot limited to water, carbon dioxide, carbon monoxide, salts,halogenated compounds, metal oxides, sulfur containing species, nitrogencontaining species (e.g., nitrogen oxides), etc., and mixtures thereof.

A→B+C  equation 1

A→B+C+D  equation 2

A+E→B+C  equation 3

A+E→B+C+D  equation 4

In some embodiments, molecular oxygen is the desired oxidizing agentspecies “C” as follows:

A→B+O₂

A→B+O₂ +D

A+E→B+O₂

A+E→B+O₂ +D

The chemical species A includes but is not limited to chemical compoundsthat contain an oxygen-oxygen bond including but not limited to hydrogenperoxide, peroxo compounds, organic peroxides, organic hydroperoxides,peracids, inorganic peroxides, inorganic hydroperoxides, percarbonates,perborates, perphosphates, persulfates, peroxyhydrate salts, oxygeninclusion compounds, certain oxides, and mixtures thereof. The chemicalspecies A can also include compounds that complex or bind molecularoxygen, hydrogen peroxide, ozone, oxygen radical or dioxygen radical.The chemical species A can also include oxygen rich compounds such aschlorate salts, bromate salts, iodate salts, perchlorate salts,periodate slats, permanganate salts, chromate salts, etc.

In some embodiments, “A” includes calcium peroxide, magnesium peroxide,barium peroxide, zinc peroxide, cadmium peroxide, strontium peroxide,lithium peroxide, sodium peroxide, potassium peroxide, lithium nickelperoxide, potassium superoxide, sodium percarbonate, potassiumpercarbonate, calcium percarbonate, magnesium percarbonate, sodiumperborate, sodium perborate tetrahydrate, potassium perborate, calciumperborate, magnesium perborate, potassium permanganate, sodiumpersulfate, potassium persulfate, and other peroxyhydrate salts such aspotassium pyrophosphate peroxyhydrates and sodium sulfate-hydrogenperoxide-sodium chloride adduct, and mixtures thereof. In someembodiments, “A” includes calcium peroxide, magnesium peroxide, lithiumperoxide, potassium superoxide, sodium peroxide, zinc peroxide, sodiumpercarbonate, sodium perborate, potassium persulfate and sodiumpersulfate, silver oxide, gold oxide and mixtures thereof. Peroxyhydratesalts useful in the present disclosure are described in U.S. Pat. Nos.3,650,705, 3,140,149, 4,323,465, and 4,005,182, wherein the entirety ofeach patent document is hereby incorporated by reference.

In some embodiments, catalyst “E” includes one or more of transitionmetal oxides, transition metal compounds, manganese oxides, manganesecompounds, potassium permanganate, copper oxides, copper compounds,nickel oxides, vanadium oxides, vanadium compounds, iron oxides, ironcompounds, arsenic compounds, lead oxides, lead compounds, tin oxides,tin compounds, and mixtures thereof. An optional catalyst may be addedto the oxygen generating compound in concentration of 0.1-10% wt. andmore preferably from 1-5% wt.

As mentioned above, a composition A that decomposes into an oxidizingagent species C can be in a solid, liquid or gas form. In someembodiments, the composition is in solid form.

Nonlimiting examples of decomposition reactions of a solid compositionthat generate a gaseous oxidizing agent include:

CaO_(2(s))→CaO_((s))+0.5O_(2(g))

ZnO_(2(s))→ZnO_((s))+0.5O_(2(g))

MgO_(2(s))→MgO_((s))+0.5O_(2(g))

2KO_(2(s))→K₂O_((s))+1.5O_(2(g))

Li₂O_(2(s))→Li₂O_((s))+0.5O_(2(g))

Na₂CO₃·1.5H₂O_(2(s))→Na₂CO_(3(s))+1.5H₂O_((g)+)0.75O_(2(g))

K₂S₂O_(8(s))→K₂S₂O_(7(s))+0.5O_(2(g))

NaBO₃·H₂O_((s))→NaBO_(2(s))+H₂O_((g))+0.5O_(2(g))

A nonlimiting example of a catalytic reaction (catalyst=MnO_(2(s)))includes the following:

CaO_(2(s))+0.05MnO_(2(s))→CaO_((s))+0.5O_(2(g))+0.05MnO_(2(s))

Li₂O_(2(s))+0.05V₂O_(3(s))→Li₂O_((s))+0.5O_(2(g))0.05V₂O_(3(s)).

An example of selecting a composition A that decomposes into anoxidizing agent species C was illustrated with zinc peroxide.Thermogravimetric analysis (TGA) was performed on zinc peroxide byheating zinc peroxide at a rate of 10° C./min under nitrogen (25 mL/min)in a TA 5500 Thermogravimetric Analyzer. The data showed that the sampledecomposed at 200° C. Thermal Desorption-Mass Spectroscopy (TD-MS) ofthe samples heated in helium flow at 10° C./min. showed the sample ofzinc peroxide decomposed to give the desired oxygen as the majorcomponent together with some amounts of water and traces of carbondioxide. Data was also generated to show the rate of weight loss of ZnO2when heated at 100° C., 120° C. and 140° C. as well as oxygen releasefrom zinc peroxide when heated at 130° C. To help actively control therelease of oxygen into a hard disk drive interior gas space, zincperoxide could be disposed inside a disk drive with a heater since itdecomposes at a temperature above typical operating temperatures of ahard disk drive.

In some embodiments, as illustrated by the equations 5-8 below, thechemical composition that generates an oxidizing agent species is amixture of two or more chemical species F and G that react with eachother to generate the oxidizing agent species C.

F+G→B+C  equation 5

F+G→B+C+D  equation 6

F+G+E→B+C  equation?

F+G+E→B+C+D  equation 8

where F and G are reactants that when reacting with each other generatean oxidizing agent species C in the electronic device (e.g., hard diskdrive), B is a byproduct of the reaction, C is an oxidizing agentspecies, D is a secondary product of reaction, and E is either acatalyst a stabilizer or a barrier. As mentioned above, F and G can eachindependently be in the form of a solid, liquid or gas state. In someembodiments, the chemical composition F that generates an oxidizingagent species C reacts with a gaseous or liquid species G to produce anoxidizing agent species C. Depending on the conditions (e.g.,temperature and pressure) within the interior of an electronic device(e.g., hard disk drive), B, C, and D can each independently be in theform of a solid, liquid, or gas.

F and G can each be selected to provide a desirable rate of reaction andgenerate a desirable concentration of the gaseous oxidizing agentcomponent. In some embodiments, at least one reactant comprises at leastone peroxide. In some embodiments, a first reactant is chosen fromcalcium peroxide, lithium peroxide, sodium peroxide, potassium peroxide,sodium chlorate and mixtures thereof. In some embodiments, a secondreactant is chosen from liquid water, gaseous water, gaseous carbondioxide, solid iron and mixtures thereof. Nonlimiting examples ofreactive systems are illustrated as follows:

CaO_(2(s))+CO_(2(g))→CaCO_(3(s))+0.5O_(2(g))

Li₂O_(2(s))+CO_(2(g))→Li₂CO_(3(s))+0.5O_(2(g))

CaO_(2(s))+H₂O_((l))→Ca(OH)_(2(s))+0.5O_(2(g))

Li₂O_(2(s))+H₂O_((l))→2Li(OH)_((s))+0.5O_(2(g))

Na₂O_(2(s))+H₂O_((l))→2Na(OH)_((s))+0.5O_(2(g))

2KO_(2(s))+H₂O_((l))→2K(OH)_((s))+1.5O_(2(g))

Na₂O_(2(s))+H₂O_((g))→2Na(OH)_((s))+0.5O_(2(g))

2KO_(2(s))+H₂O_((g))→2K(OH)_((s))+1.5O_(2(g))

Na₂O_(2(s))+CO_(2(g))→Na₂CO_(3(s))+0.5O_(2(g))

2NaClO_(3(s))+2Fe_((s))→2NaCl_((s))+2FeO_((s))+2O_(2(g))

K₂O_(2(s))+H₂O_((l))→2K(OH)_((s))+0.5O_(2(g))

In some embodiments, as similarly described above with respect to thedecomposition of A, one or more of the following can be used incombination with the selection of F and G: 1) a catalyst to acceleratethe reaction of F and G, 2) a stabilizer to slow down the reaction of Fand G, and/or 3) a barrier film or material, to control the rate thediffusion oxidizing agent species C. For example, the rate of suchreactions systems may be altered from those of pure compounds by theaddition of catalyst materials, stabilizers and/or barrierfilms/materials to maintain the desired oxygen partial pressure insidethe drive. Possible catalysts include but are not limited to transitionmetal oxides and compounds, manganese oxides, manganese compounds,potassium permanganate, copper oxides, copper compounds, nickel oxides,vanadium oxides, vanadium compounds, iron oxides, iron compounds,arsenic compounds, lead oxides, lead compounds, tin oxides and tincompounds.

As used herein, a “stabilizer” refers to a material that can slow down(partially inhibit) the generation of the gaseous oxidizing agent. Forexample, a stabilizer can slow down the reaction of a composition thatcan actively generate a gaseous oxidizing agent component as describedherein in the context providing gaseous oxidizing agent component to theinterior of an electronic device over its commercial life. A stabilizercan be in a variety of physical forms such a coating and/or a discreteingredient.

In some embodiments, the stabilizer can be present as a coating on oneor more compounds that can actively decompose to generate the gaseousoxidizing agent component and/or one or more reactants that can reactwith one or more other reactants to generate the gaseous oxidizing agentcomponent. In some embodiments, a stabilizer coating can be made ofmaterial that includes one or more phosphate salts (e.g., sodiumphosphate, sodium polyphosphate, and the like), one or more phosphateanalogues, one or more ethylene oxide oligomers, one or more ethyleneoxide polymers, and combinations thereof. Non-limiting examples of aphosphate salt according to the present disclosure include alkali-metalsalts such as sodium phosphate. Alkali-metal phosphate salts include avariety of salts of an alkali metal and phosphate, where “phosphate” asused herein also includes di-, tri-, tetra-, and polyphosphates. Suchsalts can be anhydrous (water-free) and/or hydrated. A phosphateanalogue is structurally and functionally similar to a phosphate saltused as a stabilizer according to the present disclosure. Non-limitingexamples of an ethylene oxide polymer according to the presentdisclosure include polyethylene glycol and the like.

In some embodiments, the stabilizer can be present as a discreteingredients in admixture with one or more compounds that can activelydecompose to generate the gaseous oxidizing agent component and/or withtwo or more reactants that can react with each other to generate thegaseous oxidizing agent component. In some embodiments, a discrete,stabilizer ingredient can be made of material that includes one or morephosphate salts, one or more carboxylate salts, one or more sulfonatesalts, one or more citrate salts, one or more bicarbonate salts, one ormore permanganate salts, one or more metal oxides, one or more amides,and combinations thereof. Non-limiting examples of a bicarbonate saltaccording to the present disclosure include an alkali-metal salt such assodium bicarbonate. Non-limiting examples of a metal oxide according tothe present disclosure include one or more manganese oxides such asmanganese (II) oxide (MnO), manganese (III) oxide (Mn₂O₃), and the like.Non-limiting examples of a permanganate salt according to the presentdisclosure include an alkali-metal salt such as potassium permanganateand the like. Non-limiting examples of an amide according to the presentdisclosure include acetamide and the like. In some embodiments, watercan also be used as stabilizer depending on the gaseous oxidizing agentthat is selected. In some embodiments, water can function as both astabilizer and a catalyst depending on the gaseous oxidizing agent thatis selected. For example, some gaseous oxidizing agents water mayfunction as a stabilizer at the beginning of the decomposition and as acatalyst at the end decomposition.

One or more stabilizers and/or stabilizer coatings can be present in anamount that can slow down (partially inhibit) the generation of thegaseous oxidizing agent. In some embodiments, a stabilizer coating maybe present in amount of 10% or less, 5% or less by weight of the coatedgaseous oxidizing agent component. In some embodiments, a stabilizercoating may be present in amount in the range of 0.5-3%, or even 1-3% byweight of the coated gaseous oxidizing agent component.

In some embodiments a second chemical reaction with desired kinetics isused to produce in situ the reactant F. A non-limiting example of the insitu generation of the reactant F follows: Sodium or potassium hydrogencarbonate is decomposed to produce water and carbon dioxide;

-   -   the nascent water and carbon dioxide react then in situ with        potassium superoxide or lithium peroxide (shown below) to        generate oxygen at the desired rate.

2NaHCO_(3(s))→Na₂CO_(3(s))+H₂O_((g))+CO_(2(g))

Li₂O_(2(s))+H₂O_((g))→2LiOH_((s))+0.5O_(2(g))

Li₂O_(2(s))+CO_(2(g))→Li₂CO_(3(s))+0.5O_(2(g))

Some chemical species may exist in multiple forms for example water mayexist and react in either the liquid form and/or the gas form, dependingon the temperature.

In some embodiments, the active oxygen generating device comprises areservoir containing water, an ultra-micro-pump capable of dispensing0.01-10 microliter of water per pulse to a container with a reactiveoxygen generating compound. Illustrative reactive oxygen generatingcompounds include potassium superoxide, potassium peroxide, sodiumperoxide and lithium peroxide. An optional catalyst may be added to theoxygen generating compound in concertation of 0.1-10% wt., e.g., from1-5% wt. Illustrative catalysts include metal oxides such as potassiumpermanganate, manganese oxide, cobalt oxide, copper oxide, iron oxide,vanadium oxide and combinations thereof. Illustrative reactions are asfollows:

Li₂O_(2(s))+H₂O_((l))→2Li(OH)_((s))+0.5O_(2(g))

Na₂O_(2(s))+H₂O_((l))→2Na(OH)_((s))+0.5O_(2(g))

K₂O_(2(s))+H₂O_((l))→2K(OH)_((s))+0.5O_(2(g))

2KO_(2(s))+H₂O_((l))→2K(OH)_((s))+1.5O_(2(g))

In some embodiments, an electronic device according to the presentdisclosure can include a generating device configured to activelydecompose the composition or to cause two or more reactants to react togenerate the gaseous oxidizing agent component.

Non-limiting examples of active oxygen production techniques include 1)a heater to accelerate the reaction rates of oxygen liberatingcompounds; 2) electrochemical cell to use voltage and electric currentto stimulate oxidation/reduction reactions to produce oxygen; and 3) adevice that dispenses water in a metered manner to a reactive oxygengeneration compound.

With respect to heating a composition as described herein to activelycause a composition to generate gaseous oxidizing agent component, ithas been discovered that one or more oxygen-generating materials, suchas zinc peroxide, can possess a “memory” in regard to its oxygengeneration rate. For example, it has been observed that at a fixedtemperature such materials show an initial, relatively slow rate ofoxygen output (e.g., ten times slower than the peak rate of oxygenoutput) followed by an increase in oxygen output (moles of oxygen permole of active oxygen-generating material that remains) as theoxygen-generating material is consumed and ultimately followed by adecrease in oxygen output. While not being bound by theory, it isbelieved that the material has an inherent history (“remembers”) of howlong it has been exposed to that temperature and responds with achanging oxygen output over its long-term use in an electronic devicesuch as an HDD.

In more detail, consider a given electrical input power to heat acomposition to generate gaseous oxidizing agent component. It is assumedthat a fixed power level is supplied for a constant “power-on” duration,thereby producing a fixed temperature for a given system configuration.At the outset, the composition may produce relatively little oxygen, butwould produce more oxygen as the composition is exposed to the fixedtemperature and increase in oxygen production rate until to a peakoxygen production rate is achieved. The peak oxygen production rate canbe reached at some point during the service life of the electronicdevice (e.g., from 5 to 7 years, or even longer). In some embodiments,the peak oxygen production rate can be reach at about the middle of theservice life of the electronic device (e.g., at about 2.5 to 3.5 years).After reaching the peak oxygen production rate, the oxygen productionrate tends to decrease as the mole fraction of unconsumedoxygen-generating material decreases. Such increase and decrease ofoxygen production rate is considered “unsteady,” which can result in oneor more disadvantages as described below.

As just described, the output of a generating device configured toactively cause the composition to generate a gaseous oxidizing agentcomponent (e.g., oxygen) can vary considerably over the lifetime of theelectronic device due to the “memory” of the composition. All else beingequal, the oxygen production rate increases approximately exponentiallyas the temperature of the oxygen-generating composition increases.Increasing the input power can increase the temperature of theoxygen-generating composition correspondingly, which can increase therate that oxygen is generated. Accordingly, to accommodate thepreviously described, unsteady nature of oxygen production rate that canbe caused by the “memory” of the composition, the generating device canbe configured to supply/consume relatively more electrical energy tomeet oxygen demand early in the service life of the electronic device ascompared to later in its service life after the composition has “aged”due to exposure to elevated temperature (discussed above).Unfortunately, the input power that may be needed to supply theappropriate power to the composition early in the service life of theelectronic device may be constrained by one or more of 1) the capabilityof the on-board electrical power supply, 2) by power usage limitsimposed by the end-user of the electronic device, 3) temperaturelimitations in one or more materials used to construct the generatingdevice, or 4) undue depletion of the oxygen-generating composition ifthe temperature of the composition increases too much. Such constraintscan create uncertainty as to whether sufficient oxygen can be created,which may cause the oxygen generator device to be sub-optimal for atleast a portion if not a majority of its service life.

According to the present disclosure, at least one other solution toaccommodate the “memory” of the composition (discussed above) includes“pre-conditioning” the oxygen-generating composition by exposing thecomposition to one or more elevated temperatures to consume an amount ofthe oxygen-generating composition and provide a more uniform oxygengeneration profile over the service life of the electronic device.Pre-conditioning temperatures can include exposing the oxygen-generatingcomposition to one or more temperatures for a time period so as to“skip” at least portion of the early service life of the electronicdevice that includes an oxygen-generating composition has not been“pre-conditioned” as described herein. Advantageously, pre-conditioningthe oxygen-generating composition may cause the composition to provide arelatively more uniform oxygen generation profile when heated over thelifetime of the electronic device. In addition, pre-conditioning theoxygen-generating composition according to the present disclosure mayhelp mitigate or avoid one or more the constraints mentioned above.

In some embodiments, the oxygen-generating composition can bepre-conditioned by heating the composition to one or more“pre-conditioning” temperatures for a time period that causes anincrease in rate of weight loss of the composition for a referencetemperature. In more detail, exposing the composition to one or morepre-conditioning temperatures as described herein causes the rate ofweight loss of the composition to increase as determined for a referencetemperature from a first rate of weight loss of the composition to asecond rate of weight loss of the composition. The second rate of weightloss can be selected to be less than a maximum rate of weight loss atthe reference temperature.

The reference temperature can be one or more temperatures selected thatcorrespond to temperatures used to generate oxygen during the servicelife of the electronic device. Non-limiting examples of the referencetemperature include a temperature from 100° C. to 160° C., or even 100°C. to 130° C.

Pre-conditioning can be performed using a wide variety of heatingtechniques such as an oven, which is readily and commercially available.

A pre-conditioning temperature can be selected to consume a desiredamount of the composition “skip” at least portion of the early servicelife as described above. Determining the amount of material to consumedepends on the specific composition selected (e.g., zinc peroxide) andcan be determined by reference to charts that show “rate of reaction”versus conversion. Non-limiting examples of the pre-conditioningtemperature include one or more temperatures from 100° C. to 160° C., oreven 100° C. to 130° C.

A pre-conditioning time period can be selected as desired depending onthe selected pre-conditioning temperature. Non-limiting examples of thepre-conditioning time period include a time period from 1 second to 24hours, from 10 seconds to 5 hours, or even from 10 seconds to 2 hours.

The rate of weight loss of the composition can be reported in anydesired units (e.g., percent weight loss per unit time) and can bedetermined using a variety of techniques such as a thermogravimetricanalyzer.

FIGS. 1A and 1B show a schematic representation of active devicesconfigured to actively decompose a composition using thermal energy togenerate a gaseous oxidizing agent component.

FIG. 1A shows a basic embodiment of a device 100 that includes at leastone heater 110 in thermal contact with a solid composition 105. Thesolid composition can be any solid composition selected to decomposewhen heated to a given temperature as described herein to decompose thecomposition and generate the gaseous oxidizing agent component.

A device such as 100 can include one or more additional components suchas a temperature sensing device, power source, insulation, a containeror barrier materials (e.g., metal foil) to contain the components (e.g.,heater) and the composition, and a membrane to allow oxygen and othergasses to escape. A thermocouple or any other temperature sensing devicecan be used for feedback control of temperature, which can be used forthe predetermined kinetics to generate a gaseous oxidizing agentcomponent. Also, a heater can be selected to be in electricalcommunication with control hardware of an electronic device so that itcan operate in an on-off manner to heat the composition to generate agaseous oxidizing agent component. A heater can be used to joule heatthe oxygen generating composition. Depending on the temperature desired,heater power can be determined to provide a desirable rate of oxygengeneration for a given application. It has been observed that there canbe a cooling effect if a heater system is directly exposed to theinterior of an electronic device such as a hard disk drive during driveoperation as compared to if the heater system is enclosed in containersuch as an environmental control module (ECM) that is disposed insidethe electronic device. Thus, there can be a power savings due to theinsulating effect of the ECM, especially as the power increases. Also,it has been observed that 1% oxygen concentration and 10% oxygenconcentration had relatively little impact on the temperature differencefor a given power setting when the heater system was exposed to theinterior of a hard disk drive.

In some embodiments, a heater includes a compound heater, which is asmall furnace that may include a heater element, a temperature probe, achamber to contain the oxygen liberating compounds. In some embodiments,a compound heater can include a gas permeable membrane to allow oxygenproduced to transport to the main interior volume of the electronicdevice (e.g., HDD). A compound heater can be a joule heating device thatoperates by injecting electric current into the heating element to raisethe temperature of the oxygen liberating chemical compound to the rangeof temperatures needed to liberate oxygen at the desired rate.

An oxygen generation device was built with 500 mg of zinc peroxidepowder similar to that shown in FIG. 1A with a thermocouple in contactwith the powder, all of which was wrapped in aluminum foil. The devicewas placed inside a hard disk drive and powered to reach outer surfacetemperature of the generator of 100° C. or 120° C. for different lengthsof time. The composition of the gas of the drive and a control drivewith no device was measured with a residual gas analyzer. It wasobserved that the oxygen partial pressure increased in the sealed drivesafter powering the zinc peroxide heater versus the control. The oxygencontent of two drives increased from 1% to 10% and 18%, respectively,after the zinc peroxide heater was powered for a different length oftime while the oxygen of three control drives containing with no oxygengenerator remains at initial fill of 1%.

FIG. 1B shows a cross-section schematic of another embodiment of adevice 150 for actively generating a gaseous oxidizing agent component.As shown in FIG. 1B, shows plates 105 of solid composition (e.g., oxide)surrounding a single heater 110. Thermally conductive material 111 canseparate adjacent plates 105 and heater 110 from adjacent plates 105. Awide variety of thermally conductive material and thicknesses can beused to facilitate desirable heat transfer. Nonlimiting examples ofthermally conductive material includes metal and/or ceramic materials.For example, an oxide 105 can be cast on a flexible thin ceramic fabric111 such as alumina and wrapped around the heater 110. Relatively lowheater power can activate plates 111 relatively close to the heater 110while higher power can activate plates 111 that are further away fromheater 110.

In some embodiments an electrochemical cell can be employed to activelygenerate a gaseous oxidizing agent component.

In some embodiments the electrochemical cell chemistry is based on thechemistry of certain metal-air batteries which generate oxygen gasduring the charging cycles by reducing an oxygen-rich chemical speciessuch as metal oxide or peroxide at the air battery cathode via a “redox”reaction. Metal-air batteries use atmospheric oxygen to react withvarious species to produce both electricity and metal oxide or peroxidecompounds on the cell's cathode. Next during the re-charge cycle,electricity is pumped into the cell and the reverse chemical processesliberates oxygen from the cell's cathode (anode when run in rechargingdirection). According to the present disclosure, a metal-air batterychemistry charge cycle can be used to generate oxygen. In someembodiments, electricity can be used to generate oxygen over the courseof a single “recharge” cycle that would last the entire service life(e.g., 5 years) of an electronic device such as a hard disk drive. Insome embodiments, to help maintain viability of a metal-air battery toproduce oxygen generator after potentially long periods of inactivity(e.g., anywhere from 1 week to 5 years), a voltage across the batterycan be applied for short periods of time during periods of “inactivity”where oxygen generation is not necessarily needed in the interior spaceof an electronic device so as to prevent the formation of permanentlyinactive regions. For example, a generating device can be configured toapply a voltage across the metal-air battery if the metal-air batteryhas not undergone recharging for a time period of one week or more, twoweeks or more, or even 4 weeks or more (e.g., from two weeks to 5years). In some embodiments, a voltage can be applied across the batteryfor short periods of time such as from milliseconds up to an hour. Insome embodiments, the voltage can be applied from 1 millisecond to 30minutes, from 1 millisecond to 1 minute, or even from 1 millisecond to 1second. Also, the voltage bias can be applied in either direction(charge and/or recharge) as desired.

In some embodiments, an electrochemical cell can include at least acathode; an anode; a liquid or solid electrolyte, chemical compositionthat generates oxygen; an oxygen permeable membrane; and a power sourceand an assembly or case.

An oxygen producing cell can optionally include a gas permeable membraneon the cathode to allow liberated oxygen to escape the electrochemicalcell. The electrochemical cell can also be electrically connected to aprinted circuit board assembly (PCBA) of a hard disk drive to providethe appropriate current/voltage characteristics to control the oxygenproduction rate.

The particular chemistry could include oxygen generation from manypotential metal oxides and peroxides. In some embodiments, oxygengenerating electrochemical cells include potassium/air cells, sodium/aircells, lithium/air cells, zinc/air cells, magnesium/air cells,calcium/air cells, aluminum/air cells, iron/air cells, silicon/air cellsand combinations thereof.

In some embodiments, a metal-air battery includes a first electrode anda second electrode. The first electrode can be a metal electrode thatincludes a metal or metal alloy thereof. The metal can be chosen frompotassium, sodium, lithium, zinc, magnesium, calcium, aluminum, iron,and combinations thereof. The second electrode can be a metal oxide thatcan undergo a redox reaction to produce the gaseous oxidizing agentcomponent when the metal-air battery is recharged.

Below are examples of lithium based reactions:

Li₂O_(2(s))→O_(2(g))+2Li⁺+2e ⁻  anodic reaction

Li⁺ +e ⁻→Li_((s))  cathodic reaction

FIG. 2 shows a schematic representation of a metal-air battery that canbe used in an electronic device according to the present disclosure toactively generate a gaseous oxidizing agent component. As shown, a metalair battery 200 includes a dc power source 201, an electrolyte (Li+)202, a counter electrode with oxygen generating compound 203, a metalelectrode 204 and an oxygen permeable membrane 205.

Metal electrode 204 can be selected as desired for a given battery 200.For example, as shown in FIG. 2 , metal electrode 204 can be lithiummetal. Alternatively, metal electrode 204 can be an alloy containinglithium, or any other metal (discussed above) or alloy thereof thatwould serve to collect the ion (referred to as “ion collector”)travelling through the electrolyte 202 under the externally appliedvoltage bias while in the recharge mode where it recombines with one ormore electrons. In some embodiments, electrode 204 can include a carbonfilm (e.g., a porous carbon film) where the impinging metal ion canrecombine with an electron and become a metal atom electroplated to thesurface of the carbon.

The oxygen generating compound at electrode 203 can also be selected asdesired for a given battery 200. For example, as shown in FIG. 2 ,electrode is selected to be LiO₂ is selected to generate oxygen, e.g.,because of its relatively high energy density. Other metal oxide systemscan be selected as a metal/air battery 200 and can include any metaloxide that can undergo a redox reaction releasing O₂ and a metal ion. Ifdesired, battery 200 does not need to achieve an open circuit voltageafter oxygen generation.

The composition and thickness of an electrolyte film such as 202 can bechosen such that the oxygen generation rate is equal to or greater thanthe maximum oxygen consumption rate in the drive. The electrolyte filmcan be a solid electrolyte or liquid (e.g., a liquid, polymerelectrolyte). The vapor pressure of a liquid electrolyte at driveoperating temperatures (e.g., from 0° C. to 70° C.) can be selected toavoid a loss of electrolyte greater than 1% of the electrolyte mass.

In some embodiments, a container can be disposed within an electronicdevice, where the container contains a composition that can be activelycontrolled to generate a gaseous oxidizing agent component. Optionally,the container can be initially filled with a gaseous oxidizing agentcomponent. A container according to the present disclosure can beconfigured to allow gaseous oxidizing agent component to transfer frominside the container to the interior gas space of the housing tomaintain the gaseous oxidizing agent component at a mole fraction asdescribed herein above. Selecting a container and any related componentscan depend whether the container is initially filled with a gaseousoxidizing agent component and/or the type and amount of composition thatcan generate a gaseous oxidizing agent component. Selecting a containercan also depend on how it is incorporated into an electronic device(e.g., HDD) to release gaseous oxidizing agent into the interior spaceof the electronic device. For example, whether the container isconfigured to passively and/or actively allow gaseous oxidizing agentcomponent to be controllably transferred from inside the container tothe interior gas space of the housing.

A container that contains a composition that can be actively controlledto generate a gaseous oxidizing agent component (and that is optionallyinitially filled with a gaseous oxidizing agent component) may have anydesired shape including a sphere, cylinder, cone, prism, cube, pyramidor rectangular prism, and combination thereof. Furthermore, thecontainer could be a single container or multiple separate containers.

In some embodiments, a container is disposed within an environmentalcontrol module. In other embodiments, the container is an environmentalcontrol module. The composition that can generate a gaseous oxidizingagent component can be contained in a container in such a way thatgeneration of oxygen gas would be actively controlled and passed througha permeable membrane to the internal hard disk drive interior volume,while containing the bulk solid materials (e.g., granules, pellets, andthe like) within the container.

In some embodiments, at least a portion of the container is permeable toone or more oxidizing agents such as molecular oxygen. For example, acontainer can include a membrane that is permeable to the gaseousoxidizing agent component and permits the gaseous oxidizing agentcomponent to transfer from inside the container to the interior gasspace of the housing. Oxygen permeable materials for use with or as acontainer according to the present disclosure include polymers,plastics, rubbers, elastomers, organic coatings, thin glass, and thinceramics. In some embodiments, such materials have oxygen permeabilitycoefficients between 0.0001 and 1000 (mL mm)/(m²d atm), e.g., oxygenpermeability coefficients between 0.01 and 100 (mL mm)/(m²d atm). Insome detail, illustrative permeable polymers include low densitypolyethylene (LDPE), high density polyethylene (HDPE), polypropylene(PP), polyvinylidene fluoride (PVDF), polyvinyl alcohol, ethylene vinylalcohol, nylon, polycarbonate, polyimide, and combinations thereof.Oxygen permeable membranes include single or multilayer films. In someembodiments, an oxygen permeable membrane can have a thickness fromgreater than 0 to 500 mils, from 1 to 100 mils, or even from rom 2 to 30mils. In some embodiments, oxygen permeable materials have permeationcoefficients that increase with temperature. In some embodiments, aportion of the container can be made of an oxygen impermeable materialand portion of the container is made of oxygen permeable material. Forexample, a portion of the container can be made of an oxygen impermeablematerial such as metal or glass and sealed by a lid made of an oxygenpermeable membrane that is fastened to the container in any desirablemanner (e.g. via glue).

In some embodiments, an entire container is made of an oxygen permeablemembrane. For example, such a container can be a pouch that is sealedafter the composition that can generate a gaseous oxidizing agentcomponent is place in the pouch or the container can be a vial with athreaded lid that is fastened to the container.

In some embodiments, a container may optionally contain other materialssuch as absorbents that capture secondary degradation products. Forexample, water absorbing material can be included to absorb watergenerated from the oxygen producing reaction. Such water can, e.g.,accelerate the oxygen producing reaction and/or cause the pressure inthe container to increase to an undue degree.

In some embodiments, a container can include a valve that can beactuated from a closed position to an open position to allow gaseousoxidizing agent component to flow from inside the container to theinterior gas space of the housing.

FIG. 3 shows a non-limiting example of a dual chamber container 300 witha permeation layer and micro-valve, which works like a 2-stageregulator.

Container 300 includes a composition 304 that generates a gaseousoxidizing agent component. Alternatively, the container can be filled(and pressurized) with a gaseous oxidizing agent component (e.g., up toa pressure of 5-10 atm or more) to permit controlled release ofoxidizing agent component from container to the interior space of anelectronic device (e.g., HDD) to provide oxidizing agent component inamount that maintains the concentration of the oxidizing agent componentwithin a desired range over a desired time period.

As shown, the composition 304 is disposed in a relatively large chamber303, where chamber 303 functions as an oxygen reservoir. Chamber 301 isa relatively small chamber compared to chamber 303 and functions todefine a release volume. Chamber 301 is separated from chamber 303 viaan oxygen permeable membrane 302 selected to equilibrate chambers 303and 301 in about 1 minute to 30 days, and more preferably in 1 day to 15days. A nonlimiting example of membrane 302 includes polyethylene. Asshown, a grid 310 is positioned between membrane 302 and cap 305 to helpavoid undue plastic deformation of 302 at temperature of about 60′C. Cap305 can be fastened to housing 308 via welding or bonding (e.g., gluingwith an adhesive). As shown, cap 305 is coupled to housing 308 along aninterlocking bond line. Cap 305 also includes an electro-mechanicalmicrovalve 315 (e.g., piezoelectric or bimetallic) that can becontrollably actuated (e.g., electrically activated) from a closedposition to an open position for release of oxygen from container 300.

Container 300 is small enough to fit within the cavity of an electronicdevice such as a hard disk drive or even inside and environmentalcontrol module. Container 300 can be constructed of non-elastic hardhousing 308, which can help keep the interior of an electronic deviceclean.

As mentioned, container 300 functions like a two-stage regulator toequalize pressure from large chamber 303 to small chamber 301 like atiny scuba tank (in a time period of hours or days). In someembodiments, oxygen can be released from small chamber 301 into theinterior of an electronic device every 4-6 weeks. For example, about 1cubic centimeter per week of oxygen can transfer from chamber 303 tochamber 301. Oxygen can be released from chamber 301 via valve 315relatively fast. The valve leak rate can be selected to be as low asdesired (e.g., about 0.1 cubic centimeter or less per month.

In some embodiments, the oxygen generating chemical compositiondescribed above and optionally including one or more of a heater,probes, sensors, components of the electrochemical cell and/or othermechanical or electrical components can be packaged into an assembly.The assembly can be packaged in such a way to avoid corrosion of thedrive components while maintaining gas exchange with the drive and/or toavoid the introduction of particulate or chemical contamination into theinternal gas space of the electronic device.

FIGS. 4A-4D illustrate one non-limiting embodiment according to thepresent disclosure of including a composition that can generate agaseous oxidizing agent component into a hard disk drive.

FIG. 4A shows a synoptic view of an Environmental Control Module (ECM)410 according to the present disclosure that is installed in a hard diskdrive (HDD) 400 with the top cover removed.

The ECM 410 is referred to as an “expanded” ECM because the ECM has beenmodified to accommodate a composition 412 that can generate a gaseousoxidizing agent component. An ECM 410 can include an ECM body, a solidcomposition 412 that can generate a gaseous oxidizing agent component, adesiccant 413 for absorbing moisture, a membrane (e.g., expandedpolytetrafluorethylene (ePTFE)) 416 that can contain solid particulatematter within ECM while being permeable to at least oxygen gas so thatoxygen gas can transfer from the ECM 410 to the interior of HDD 400 andbe consumed by one or more oxidizing reactions.

FIG. 4B is a partial view of HDD 400 with ECM 410 removed to show thevertical wall 450 of the PCC with flex connector.

FIG. 4C is another partial view of the expanded Environmental ControlModule (ECM) 410 in the corner of the Hard Disk Drive (HDD) 400 betweenthe Voice Coil Motor (VCM) magnet 420 and the Ramp 436. The ECM 410 sitsatop the Printed Circuit Connector (PCC) cable bulkhead (not visible).This expanded ECM 410 has internal volume suitable for containing eitheran active or passive oxygen generating system. The oxygen generatorwould be installed within the ECM. As shown in FIG. 4D, the oxygengenerator is a solid composition 412 that passively generates a gaseousoxidizing agent component In this embodiment, oxygen can be vented fromthe part 460 through an aperture covered by permeable membrane 416 shownon the top of the ECM.

The PCC bulkhead contains many electrical conduits to bring power to theVCM 420 and to allow passage of electrical signals between the recordingheads and the HDD external environment. It could allow electrical powerto be conducted to an active oxygen generator system in ECM 410.

FIG. 4D shows a cross-sectional view ECM 410. As shown, the black volumeis the available internal volume for an oxygen generator 412 as well asdesiccant 413 for HDD internal humidity control.

Alternatively, a container according to the present disclosure (e.g.,vial, capsule, etc.) could be placed a wide variety of other locationswithin a HDD besides the ECM. For example, as shown in FIG. 4A, acontainer could be placed in a cavity such as cavity 470. A cavity suchas cavity 470 may already be present in base 430 (e.g., to manage themass of cast in the corner area). As mentioned above, containersaccording to the present disclosure can contain a composition thatgenerates a gaseous oxidizing agent component and/or that can be filled(and pressurized) with a gaseous oxidizing agent component.

FIG. 5 illustrates another non-limiting embodiment according to thepresent disclosure of including a composition that can generate agaseous oxidizing agent component into a hard disk drive. As shown inFIG. 5 , the base 510 of a HDD is shown with the top cover, ECM, anddisk pack removed. The floor of base 510 may include a small well thatis under the disk pack. The well can include an oxygen generation systemsuch as an electrochemical cell to generate oxygen similar in a formsimilar to a watch battery. As shown, a permeable membrane 520 is on topof the cell for oxygen out-flux. Electrical leads at the bottom of thecell (not shown) can be potted into the base 510 for a gas-tight seal.

FIG. 6 illustrates another non-limiting embodiment according to thepresent disclosure of including a composition that can be activelycontrolled to generate a gaseous oxidizing agent component into a harddisk drive. As shown in FIG. 6 , a thin-film electrochemical oxygengenerator cell 610 attached to the back side of the vertical wall 650.An extension of the flex connector feeds the cell with electrical power.ECM removed for clarity.

FIGS. 7A-7N illustrate another non-limiting embodiment according to thepresent disclosure of including a composition that can be activelycontrolled to generate a gaseous oxidizing agent component in anelectronic device such as a hard disk drive.

FIGS. 7A and 7B show an electronic device 700 (as shown a hard diskdrive (HDD)) having a housing 703 defined by base 704 and top cover 705,thereby defining an interior gas space 706. Electronic device 700includes one or more electronic components (e.g., disk media 707 andactuator arm 708) disposed within the housing 703.

FIG. 7A shows an isometric view of electronic device 700 with the oxygengenerator/ECM assembly 710 installed. The top cover of the HDD 700 isremoved for illustration purposes. The ECM frame can anchor onto PCCBulkhead (underneath the ECM) with pins. As discussed below, the ECM 710contains desiccator 735 and an generating device 720 that includes acomposition (e.g., zinc peroxide) that can generate a gaseous oxidizingagent component. Electrical power can be routed through the ECM framefrom the PCC to the heater assembly/device 720. As discussed below,heater device 720 includes a helical heating coil and has a metallized,gas-tight seal to keep the composition (e.g., zinc peroxide) dry atleast until use.

FIG. 7B shows a cross-sectional view of the electronic device 700through the ECM 710 and with a HDD top cover 705 installed.

FIG. 7C shows a close-up of the view in FIG. 7B.

The ECM 710 includes an ECM outer frame 711 and an inner wall 712 toseparate the desiccator module 730 from the heater device 720. The innerwall 712 can help insulate the desiccator module 730 from the heaterdevice 720 so that the desiccator module 730 is not heated to an unduedegree, thereby causing moisture to transfer out of the desiccant 735.The ECM 710 is held in place vertically with the assistance of the topcover 705 gasket bead 750. The ECM 710 also includes a circular inletdiffuser filter 760 that aligns with a helium fill hole and filtersincoming gas when filling the drive during assembly.

As shown, the desiccator module 730 is a discrete unit that can slipfits into ECM frame 711 and inner wall 712. Alternatively, desiccatormodule 730 could be an integral with the ECM frame 711. As mentioned,desiccator module 730 contains desiccant for relative humidity (RH)control. Desiccator module 730 can also contain activated carbons forvolatile organic compound (VOC) control.

Heater device 720 includes a composition 723 that can actively generatea gaseous oxidizing agent component. Generating device 720 is configuredto actively cause the composition 723 to generate the gaseous oxidizingagent component. Generating device 720 also includes one or more heatingelements 725 in thermal contact with the composition 723, where the oneor more heating elements are in electrical communication with a powersource (e.g., like PCC 450 in FIG. 4B) that is configured to apply powerto the one or more heating elements 725 to resistively heat the elementsand transfer the heat to the composition 723 and heat it to atemperature that causes the composition to generate the gaseousoxidizing agent component. FIG. 7D shows an isometric top view of thewhole oxygen generator ECM assembly 710.

FIG. 7E shows an isometric bottom view of the whole oxygen generator ECMassembly 710 illustrating electrical contacts 765, which can mate withcorresponding ones on the PCC bulkhead.

FIG. 7F shows another isometric bottom view of the whole oxygengenerator ECM assembly 710 illustrating electrical contacts 765, whichcan mate with corresponding ones on the PCC bulkhead.

FIG. 7G shows a cross-sectional view of the whole oxygen generator ECMassembly 710.

FIG. 7H shows an exploded view of the whole oxygen generator ECMassembly 710 including electrical contacts 766 on heater module 720.

FIG. 7I shows an isometric top view of the ECM frame 711 that will holdboth the desiccator module 730 and the oxygen generator module 720. Itwill reside in the HDD atop the PCC bulkhead. The structure 767 is aflex circuit to conduct electrical power to the oxygen generator 720.

FIG. 7J is an isometric view of the top of the desiccator module 730. Asshown, it is a gas-tight box with a soft aluminum seal that hold thedesiccant. The seal helps keep the desiccant dry on the manufacturingfloor. The desiccator is activated by breaking the seal 761.

FIG. 7K is an isometric view of the bottom of the desiccator module 730.FIG. 7L is an isometric view of one end of the heater module 720.

FIG. 7M is an isometric view of the other end of the heater device 720having the electrical contacts 766.

FIG. 7N is a cross-sectional view of the generating device/heater module720, which is considered a relatively, high aspect ratio oxygengenerator device.

The composition 723 can be loose in a container or in a form of athree-dimensional shape such a sphere, cylinder, square, and the like.As shown in FIG. 7N, composition 723 is in the form of a hollow cylinderhaving a length 731, an inner radius 732, an outer radius 733, areference center 734, a first end 736, and a second end 737.

As mentioned, generating device 720 includes one or more heatingelements 725 in thermal contact with the composition 723. As shown, theone or more heating elements 725 are in the form of a helical coil 725surrounded by an oxygen generating solid such as zinc peroxide. Coil 725has ends that correspond to the ends of the composition 723. That is, afirst end 736 and a second end 737 opposite the first end. As shown, thecoil 725 includes electrical power contacts 766 located on the first end736.

On the second end 737 is an oxygen permeable membrane 721 (e.g., apolytetrafluorethylene (PTFE) membrane) to permit at least oxygen gas totransfer out of device 720 as the oxygen is generated, out of ECMassembly 710 and into interior gas space 706 of electronic device 700.Membrane 721 may also be selected to permit the transfer of one or moreother gases therethrough and, optionally, not permit transfer ofparticles therethrough so as to prevent any particles transferring frominside device 720 into the interior gas space 706 to avoid any undueparticle contamination.

Generating device 720 can include thermal insulation to help insulatethe interior of device 720 relative to the rest of ECM assembly 710and/or relative to the interior gas space 706 of electronic device 700.Providing the generating device 720 with insulation can help managepower supply and consumption of electronic device 700 (e.g., reducepower that is supplied to heat the composition to generate a gaseousoxidizing agent component) and/or manage the temperature profile ofcomposition 723. Managing the temperature profile of the composition 723can help manage the consumption of the composition 723 and/orheat-of-reaction generated thereby. Managing the consumption ofcomposition 723 can help avoid premature consumption due to, e.g., unduetemperature increases at one or more points throughout the composition723.

In some embodiments, the generating device 720 can include a housingthat has thermal insulation properties to insulate the composition 723relative to one or more other portions of electronic device 700. Asshown in FIG. 7N, generating device 720 includes housing 727 that hasthermal insulating properties. Non-limiting examples of providinghousing 727 with thermal insulation properties include ceramic housingmaterials (e.g., film), plastic housing materials (e.g., film), and/orcreating a space in housing 727 and introducing thermal insulatingmaterials (e.g., one or more of vacuum, plastic materials such as beads,or ceramic materials such as beads) into said space. In someembodiments, housing 727 can be film or a hollow structure having afirst (inner) wall and a concentric, second (outer) wall defining aspace therebetween that can be filled with thermally, insulating beadsand/or a have a vacuum. For example, 727 can schematically represent afilm having thickness from one side 738 to another side 739.

Alternatively, housing 727 can schematically represent hollow structurehaving a first (inner) wall 738 and a concentric, second (outer) wall739 defining a space therebetween that can be filled with thermally,insulating beads and/or a have a vacuum. Also, as shown, housing 727 ofgenerating device 720 is disposed within environmental control module710.

In more detail, as shown in FIG. 7N, housing 727 has helical coil 725disposed therein to define an interior space 726 between the housing 727and the coil 725. At least a portion (e.g., all) of the interior space726 can be filled with composition 723 that can generate a gaseousoxidizing agent component (e.g., zinc peroxide) so that the composition723 can be in thermal contact with coil 725 and be thermally heated asdesired.

FIGS. 8-10 show alternative embodiments of a generating device accordingto the present disclosure. The generating devices can be selected and/ormodified based on one or more criteria such as temperature profile(e.g., uniformity) of the composition that can actively generate agaseous oxidizing agent component when heated, heat loss from the one ormore heating elements and/or composition, and/or the power supply toachieve a given temperature profile of the composition.

FIG. 8 shows an alternative embodiment of a generating device accordingto the present disclosure, where one or more heating elements includeone or more electric wires 825 that can be heated resistively and thatare centrally disposed within a composition 823 that is in the form of acylinder having a length 831, a first end 836 and a second end 837. Thelength of the wires 825 can be selected as desired and can extend alongthe entire length 831 of the composition or as one or more discrete anddiscontinuous portions thereof. As shown, thermally insulating housing827 is similar to housing 727 discussed above and can be located aroundthe composition 823 in a thermally insulating manner. Because the one ormore electric wires 825 are a heat source centrally located within thecomposition, heat tends to radiate outward, which can reduce heat lossin some embodiments.

FIG. 9 shows another alternative embodiment of a generating deviceaccording to the present disclosure, with no outer housing like 727shown for illustration purposes and with one or more heating elementslocated on the exterior surface of composition 923. As shown in FIG. 9the one or more heating elements include at least one heating element925 disposed along at least a portion of the exterior surface 928 of thelength 931 and/or a heating element 926 at the exterior surface 928 ofthe first end 936. The length of the heating element 925 can be selectedas desired and can extend along the entire length 931 of the compositionor as one or more discrete and discontinuous portions thereof. In someembodiments, as shown, one or more heating elements 925 extend over onlya portion of the length 931, which can help manage power consumptionwhile at the same time provide desired temperature profile within thecomposition 923 so as to control the reaction that generates gaseousoxidizing agent component when heated. Heating elements located on theexternal surface of composition 923 can also facilitate manufacturing ofthe corresponding generating device. Although not shown in FIG. 9 , athermally insulating similar to housing 727 discussed above can belocated around the composition 923 in a thermally insulating manner.

FIG. 10 shows another alternative embodiment of a generating deviceaccording to the present disclosure, with one or more heating elementslocated/distributed within the composition 1023. The embodiment shown inFIG. 10 can be considered a hybrid of the embodiments shown in FIGS. 8and 9 . In more detail, as shown in FIG. 10 , one or more heatingelements include at least one heating element 1025 disposed along atleast a portion of the length 1031 with composition 1023 located oneither side of the electrical heating element 1025. The length of theone or more heating elements 1025 can be selected as desired and canextend along the entire length 1031 of the composition or as one or morediscrete and discontinuous portions thereof. In some embodiments, asshown, one or more heating elements 1025 extend over only a portion ofthe length 1031, which can help manage power consumption and heat losswhile at the same time provide desired temperature profile within thecomposition 923 so as to control the reaction that generates gaseousoxidizing agent component when heated. As shown, thermally insulatinghousing 1027 is similar to housing 727 discussed above and can belocated around the composition 1023 in a thermally insulating manner.

In some embodiments, a generating device can include a heating elementfrom a dispersed phase of electrically conducting material, which canhelp provide desirable temperature uniformity to the oxygen generatingcomposition. Non-limiting examples of such electrically conductingmaterial includes wire wool and metal foam. The oxygen generatingmaterial (e.g., zinc peroxide) can be present in the interstices. Thisway, the oxygen generating material can be in close proximity to theheating surface, thereby facilitating relatively uniform oxygenproduction and release. The density and structure of the electricallyconducting material can be provided such that there is a continuouselectrical conduction path through the heater module. For example, ahollow housing similar to module 727 could be packed with a dispersedphase of electrically conducting material and a composition that cangenerate a gaseous oxidizing agent component within its interstices.Electrical terminals could be present so that electrical current couldbe passed through the housing/module thereby heating the composition asdesired.

Active oxygen production additionally allows for the option of providingan input measurement of oxygen concentration to determine how muchoxygen production is needed to maintain the desired oxygenconcentration. This input measurement could be provided by a sensor thatdetects the concentration of the gaseous oxidizing agent component inthe interior gas space (e.g., a pressure sensor or oxygen molaritysensor within an electronic device such as a HDD). In some embodiments,an electronic device includes a) a sensor that measures theconcentration of the gaseous oxidizing agent component in the interiorgas space; and b) a controller in electrical communication with thesensor and the generating device. The controller provides instructionsto the generating device based on the measured concentration of thegaseous oxidizing agent component in the interior gas space to controlthe concentration of the gaseous oxidizing agent component in theinterior gas space. In some embodiments, a method of generating agaseous oxidizing agent component in an electronic device includes a)measuring the concentration of gaseous oxidizing agent component aninterior gas space of an electronic device; b) comparing the measuredconcentration of gaseous oxidizing agent component to a predeterminedrange of concentration of gaseous oxidizing agent component; and if theconcentration is below the predetermined range then c) activelygenerating gaseous oxidizing agent component within the interior gasspace of the electronic device if the measured concentration is below apredetermined value of concentration of gaseous oxidizing agentcomponent. If the concentration is above the predetermined range then donothing. After a predetermined period of time has passed, the processcan be repeated.

It is noted that monitoring at a given time interval for one set ofconditions can produce different results if one or more conditionschange. For example, if the oxygen consumption occurs at a slower ratefor a given time interval, then the oxygen concentration may be withinacceptable limits when monitored, but fall outside acceptable limitsshortly after being monitored, thereby causing the oxygen concentrationto become unacceptably low before the next monitoring begins. Accordingto the present disclosure, a secondary check feedback (from a sensorsuch as pressure, temperature and/or relative humidity besides oxygenconcentration measurement) can be used for feedback control. If desired,the time interval for monitoring can be adjusted accordingly as well.

In some embodiments, a composition that can actively generate a gaseousoxidizing agent component can be provided in “single-use” structuresthat are separate and discrete from each other and can be independentlyactivated to generate a desired quantity of oxygen. Each structure canbe a single use structure in that it completely consumes the compositionafter being activated and is not used afterwards. The quantity and sizeof such single use structures can be selected to provide desired oxygenconcentration throughout the service life of an electronic device or beused in combination with one or more other sources of oxygen. Anon-limiting example of such single use structures is shown in FIG. 11 .FIG. 11 shows a container 1110 such an environmental control module thatincludes a plurality of heating elements and a plurality of discretestructures 1120, 1121, 1122, 1123, etc. Each discrete structure includesa composition that can actively generate a gaseous oxidizing agentcomponent that is in thermal contact with at least one of the pluralityof heating elements 1130, 1131, 1132, 1133, respectively, such as wires.Each of the at least one of the plurality of heating elements is inelectrical communication with a power source. A corresponding generatingdevice is configured to independently apply power to the at least one ofthe plurality of heating elements of each discrete structure to heat thecomposition to a temperature that causes the composition to generate thegaseous oxidizing agent component.

1.-19. (canceled)
 20. An electronic device comprising: a) a housinghaving an interior gas space; b) one or more electronic componentsdisposed within the housing; c) a composition that can generate agaseous oxidizing agent component; and d) a generating device configuredto actively cause the composition to generate the gaseous oxidizingagent component, wherein the generating device comprises at least onemetal-air battery that is in electrical communication with a powersource that is configured to apply power to the metal-air batteryaccording to a predetermined time interval to recharge the metal-airbattery to generate the gaseous oxidizing agent component.
 21. Theelectronic device of claim 20, wherein the metal-air battery comprises aliquid or solid electrolyte, wherein the metal-air battery is optionallydisposed within an environmental control module, wherein theenvironmental control module optionally includes a gaseous oxidizingagent component permeable membrane to permit gaseous oxidizing agentcomponent to pass from inside to outside of the environmental controlmodule.
 22. The electronic device of claim 20, wherein the metal-airbattery comprises a first electrode and a second electrode, wherein thefirst electrode is a metal electrode comprising metal or metal alloythereof, wherein the metal is chosen from potassium, sodium, lithium,zinc, magnesium, calcium, aluminum, iron, and combinations thereof, andwherein the second electrode is a metal oxide that can undergo a redoxreaction to produce the gaseous oxidizing agent component when themetal-air battery is recharged.
 23. The electronic device of claim 22,wherein the first electrode further comprises a carbon film.
 24. Theelectronic device of claim 20, wherein the generating device isconfigured to apply a voltage across the metal-air battery if themetal-air battery has not undergone recharging for a time period of twoweeks or more.